Treatment of mineral and vegetable oils.



runrrn srarns PATENT oration JOHN JAMES HOOD AND ALFRED GORDON SALAMON, OF LONDON, ENGLAND, ASSIGNORS TO THE OIL REFINING IMPROVEMENTS COMPANY, LIMITED, OF GLASGOW, SCOT- LAND.

TREATMENT OF MINERAL AND VEGETABLE OILS.

ocasai.

No Drawing.

To all "whom it may concern:

Be it known that we, JOHN JAMES H001) and ALFRED GORDON SALAMON, subjects of the King of Great Britain, both residing at l Fenchurch avenue, London, England, have invented new and useful Improvements in the Treatment of Mineral and Vegetable Oils, of which the following is a specification.

The object of the invention is to efiiciently decolorize, and in some instances deodorize, for commercial purposes, crude oil whether mineral oil or vegetable oil, such for instance as cotton seed oil and wood oil, or the fractionated products thereof. This is effected by using as a filtering material for the crude or fractionated oil chemically precipitated alumina which has been very thoroughly washed dried and ignited below bright redness, 2'. c. to a dull red heat so as to render it practically anhydrous. When alumina is precipitated it appears in the trihydrate form, its formula being Al O .3H O and these three molecules of water are removed by the heating. Further, in the event of commercial requirements demanding a cheaper material than the chemically precipitated alumina, it is found that highly satisfactory results can be obtained by employing bauxite (which is the natural equivalent of the above aluminium trihydrate). The mineral should be ground or pulverized to a condition which tests show to be the most suitable for the particular oil to be operated on and then sufiiciently heated at a dull red heat. The heating should in all cases be of such duration that the alumina may be thereby rendered practically anhydrous. Moreover in order to obtain the maximum of efficiency of the filtering material it is desirable to protect it as far as possible from atmospheric influence after heating until such time as it is brought into contact with the oil. The efficiency of the bauxite for the aforesaid purpose varies very greatly with its physical condition as well as its chemical composition, in other words upon the extent to which it consists of pure aluminium trihydrate. Thus it is found that certain bauxites of a deep red color, which might be suitable for the manufacture of aluminium or of alumina for other industrial purposes, are quite unsuitable or very inefiicient for this purpose, and

Specification of Letters Patent.

Application filed July 26, 1909.

Patented June 28, 191411.

Serial No. 509,592.

the bauxites which yield the best results are generally gray and soft and slightly greasy to the touch when rubbed and consist generally of fairly pure aluminium trihydratel In order to secure success in the employ ment of bauxite as a filtering material for oil it is necessary to proceed by way of selection and this can best be effected by making preliminary experiments upon a small laboratory scale. Some bauxites however which do not favorably respond to this laboratory test can be caused to do so by treatment with a small proportion of alkali, preferably limewatenbefore ignition, and others can be satisfactorily treated previous to ignition by moistening with a dilute acid, preferably hydrochloric. Should it be decided toemploy a bauxite treated by either of the above methods, it follows that the material to be used upon the large scale must be treated in a manner corresponding to that adopted upon the laboratory scale with, satisfactory results. It is of course obvious that any other mineral which will furnish suit-able alumina may be substituted for bauxite.

The amount of oil that can be passed through a given weight and volume of the filtering material will vary with the commercial requirements in respect of the color of the oil, but it is found that satisfactory results can be obtained by using a series of two or more filtering vessels, and ultimately using the last or catch vessel as the first vessel of the series, but we do not restrict ourselves to this method of employing the material. When the material is no longer satisfactory it can generally be again fitted for use by distilling off the absorbed oil, driving it out with steam or washing it out with light petroleum ether according to circumstances and then igniting for a suitable ried on continuously, the filtrate being run in a continuous stream from the filters to the still. The light spirit so used is collected and may be used again for similar purposes.

It is found that generally the lower the boiling point of the spirit the greater its efficiency, and also that generally a light spirit Which reacts to any marked extent when treated With bromin is not so efficient as one that Will not readily react With bromin. lVithout attempting to describe the theory underlying these observations we de sire to point out that as the result of experiments a considerable Variation is found in the efliciency of available light spirits and therefore it is necessary to make a preliminary test of the light spirit by mixing it With the oil to be treated and passing the mixture through the filtering material. The selection of the light spirit for efiicient use,

should depend upon the results thus obtained.

What We claim is 1. The process hereindescribed of deoolorizing oil Which consists in filtering it through alumina prepared by heating aluminium trihydrate and thus rendering it anhydrous.

2. The process hereindescribed of decolorizing oil Which consists in dissolving it in light petroleum spirit, filtering the solution through alumina prepared by heating aluminium trihydrate to render it anhydrous and distilling the filtrate.

JOHN JAMES HOOD. ALFRED GORDON SALAlt lON.

Witnesses:

R. B. RANsroRn,

H. J. LEWIS. 

